This is used when a router is connected to a network interface configured for "DSL/Router". The IPs are requested by the router via DHCP. This method is also used for Internet access via cable connection (broadband cable, e.g. for cable TV), where the Intra2net system is connected to the cable modem and not to a router.
The cable modem must be turned off for a short period of time when the Intra2net system is connected for the first time, or when the network card is changed. This allows it to adjust itself to the MAC address of the Intra2net system.